Answer:
A pendulum is weight suspended from a pivot so that it can swing freely
As we know that centripetal force =mv^2/r
given data is
m = mass
v = speed
r = radius
putting values we get
= 85 x 15^2 / 20
= 956.25 N
option d is correct
PE is the energy acquired by a body due to its height ! While KE is the energy acquired by the body due to its motion !
KE+PE = mechanical energy and thus mechanical energy is always conserved due to the conservation of energy which states that energy is neither created nor destroyed but only transformed !
We want a sound wave with a wavelength of 0.52 meters or a natural fraction thereof. We'll work in MKS.
w = 0.52/n
That's length. We have speed 344 meters/second so w corresponds to a frequency of
f = 344 / w = n (344/.52)
f = 661.5 n Hertz
I don't really agree with how they're saying it, but all the fundamental talk is probably trying to tell us n=1,
Answer: 661.5 Hertz
Any multiple of that will also produce constructive interference; we can go to about n=30 before we're out of the audio range.
